:root {
  --brand: #0097a7;
  --brand2: #05b8b8;
  --dark: #082333;
  --ink: #14242d;
  --muted: #667780;
  --line: #d7eaee;
  --bg: #f3fbfc;
  --white: #fff;
  --shadow: 0 26px 70px rgba(8, 35, 51, 0.14);
  --header-h: 92px;
  --content-max: 1200px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
html, body { width: 100%; max-width: 100%; margin: 0; overflow-x: hidden; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Noto Sans TC", "Microsoft JhengHei", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button, input, textarea, select { font: inherit; }

.content-width,
.section-head {
  width: min(100%, var(--content-max));
  margin-inline: auto;
}

/* ===== Header ===== */
.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: clamp(18px, 2.4vw, 38px);
  padding-inline: clamp(22px, 4.8vw, 76px);
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(18px);
  box-shadow: 0 6px 26px rgba(8, 35, 51, 0.06);
}
.brand { flex: 0 0 auto; display: flex; align-items: center; }
.brand-logo { width: clamp(230px, 20vw, 315px); height: auto; }
.main-nav {
  min-width: 0;
  flex: 1 1 auto;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(14px, 1.6vw, 30px);
  font-weight: 800;
}
.main-nav a {
  position: relative;
  flex: 0 0 auto;
  white-space: nowrap;
  font-size: clamp(13px, 0.88vw, 16px);
  transition: color 0.25s ease;
}
.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -8px;
  height: 2px;
  background: linear-gradient(90deg, var(--brand), var(--brand2));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.28s ease;
}
.main-nav a:hover { color: var(--brand); }
.main-nav a:hover::after { transform: scaleX(1); }
.menu-toggle {
  display: none;
  border: 0;
  background: transparent;
  color: var(--ink);
  font-size: 30px;
  line-height: 1;
  cursor: pointer;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  isolation: isolate;
  width: 100%;
  min-height: 100svh;
  padding-top: var(--header-h);
  overflow: hidden;
  background: #071f2d;
}
.hero-media,
.hero-overlay {
  position: absolute;
  inset: var(--header-h) 0 0;
  width: 100%;
  height: calc(100% - var(--header-h));
}
.hero-media { z-index: 0; overflow: hidden; background: #071f2d; }
.hero-bg-video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center center;
  filter: saturate(1.04) brightness(0.88);
  transform: scale(1.02);
}
.video-shimmer {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(3, 22, 35, 0.88) 0%, rgba(3, 22, 35, 0.7) 30%, rgba(3, 22, 35, 0.28) 58%, rgba(3, 22, 35, 0.04) 100%),
    radial-gradient(circle at 78% 36%, rgba(0, 190, 190, 0.14), transparent 26%);
}
.hero-overlay { z-index: 1; pointer-events: none; }
.hero-inner {
  position: relative;
  z-index: 2;
  width: min(100%, var(--content-max));
  min-height: calc(100svh - var(--header-h));
  margin-inline: auto;
  display: flex;
  align-items: center;
  padding: clamp(64px, 8vh, 110px) clamp(28px, 4vw, 58px) clamp(90px, 11vh, 130px);
}
.hero-content { width: min(720px, 68%); color: #fff; }
.eyebrow {
  margin: 0 0 18px;
  color: #09c6c6;
  font-size: clamp(17px, 1.4vw, 25px);
  font-weight: 900;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.eyebrow.dark { color: var(--brand); }
.hero h1 {
  margin: 0;
  font-size: clamp(88px, 10.4vw, 168px);
  line-height: 0.92;
  letter-spacing: -0.065em;
  font-weight: 900;
}
.hero h1 span { color: #08b8ba; }
.hero h2 {
  margin: 28px 0 18px;
  font-size: clamp(38px, 4vw, 65px);
  line-height: 1.16;
  letter-spacing: -0.03em;
}
.hero .lead {
  max-width: 680px;
  margin: 0;
  font-size: clamp(18px, 1.55vw, 26px);
  font-weight: 650;
  line-height: 1.8;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 18px; margin-top: 38px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 56px;
  padding: 13px 28px;
  border-radius: 999px;
  font-weight: 900;
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease;
}
.btn:hover { transform: translateY(-3px); }
.btn-primary {
  color: #fff;
  background: linear-gradient(135deg, #0089a6, #06bcb8);
  box-shadow: 0 12px 30px rgba(0, 151, 167, 0.25);
}
.btn-primary:hover { box-shadow: 0 18px 36px rgba(0, 151, 167, 0.35); }
.btn-outline { color: #fff; border: 1.5px solid rgba(255, 255, 255, 0.82); background: rgba(255,255,255,0.04); }
.btn-light { color: var(--brand); background: #fff; }
.scroll-hint {
  position: absolute;
  z-index: 3;
  left: 50%;
  bottom: 28px;
  transform: translateX(-50%);
  display: grid;
  justify-items: center;
  gap: 8px;
  color: #fff;
  font-weight: 700;
  font-size: 14px;
}
.scroll-hint span {
  width: 26px;
  height: 42px;
  border: 2px solid rgba(255,255,255,0.9);
  border-radius: 999px;
  position: relative;
}
.scroll-hint span::after {
  content: "";
  position: absolute;
  top: 8px;
  left: 50%;
  width: 4px;
  height: 8px;
  border-radius: 999px;
  background: #fff;
  transform: translateX(-50%);
  animation: scrollDot 1.5s ease-in-out infinite;
}
@keyframes scrollDot { 0%,100%{transform:translate(-50%,0);opacity:.55} 50%{transform:translate(-50%,10px);opacity:1} }

/* ===== Shared sections ===== */
.section {
  width: 100%;
  padding: clamp(76px, 8vw, 120px) clamp(22px, 5vw, 72px);
  scroll-margin-top: var(--header-h);
}
.light-section { background: #fff; }
.interface-section,
.specs-section,
.motion-section { background: var(--bg); }
.section-head { text-align: center; margin-bottom: 46px; }
.section-head h2,
.copy h2,
.motion-copy h2,
.cta-section h2 {
  margin: 0;
  font-size: clamp(38px, 4.6vw, 66px);
  line-height: 1.15;
  letter-spacing: -0.04em;
}
.section-head > p:last-child { max-width: 760px; margin: 18px auto 0; color: var(--muted); font-size: 18px; }

/* ===== Cards ===== */
.feature-grid,
.function-grid,
.price-grid {
  display: grid;
  gap: 24px;
}
.feature-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.function-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.price-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); max-width: 900px; }
.feature-card,
.function-card,
.price-card,
.spec-card {
  min-width: 0;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: #fff;
  box-shadow: 0 18px 45px rgba(8, 35, 51, 0.08);
}
.feature-card,
.function-card { padding: 30px; transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease; }
.feature-card:hover,
.function-card:hover,
.price-card:hover { transform: translateY(-5px); border-color: rgba(0,151,167,.35); box-shadow: var(--shadow); }
.feature-card span,
.function-card strong { color: var(--brand); font-size: 15px; letter-spacing: .12em; }
.feature-card h3,
.function-card h3 { margin: 12px 0 8px; font-size: 24px; }
.feature-card p,
.function-card p { margin: 0; color: var(--muted); }

/* ===== Operation interface ===== */
.split {
  display: grid;
  grid-template-columns: minmax(300px, 0.9fr) minmax(0, 1.4fr);
  align-items: center;
  gap: clamp(42px, 6vw, 88px);
}
.copy { min-width: 0; }
.copy > p:not(.eyebrow) { color: var(--muted); font-size: clamp(18px, 1.5vw, 23px); }
.check-list { list-style: none; padding: 0; margin: 26px 0 0; display: grid; gap: 14px; }
.check-list li { position: relative; padding-left: 34px; font-size: 18px; font-weight: 800; }
.check-list li::before { content: "✓"; position: absolute; left: 0; color: var(--brand); font-weight: 900; }
.ui-strip {
  min-width: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  align-items: start;
}
.ui-strip img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  border-radius: 22px;
  box-shadow: 0 18px 44px rgba(8, 35, 51, 0.15);
  transition: transform .25s ease, box-shadow .25s ease;
}
.ui-strip img:hover { transform: translateY(-4px) scale(1.01); box-shadow: var(--shadow); }

/* ===== Specs ===== */
.spec-card { overflow: hidden; }
.spec-row { display: grid; grid-template-columns: 180px minmax(0, 1fr); gap: 28px; padding: 24px 30px; border-bottom: 1px solid var(--line); }
.spec-row:last-child { border-bottom: 0; }
.spec-row span { color: var(--brand); font-weight: 900; }
.spec-row b { font-weight: 750; }

/* ===== Video ===== */
.motion-inner {
  display: grid;
  grid-template-columns: minmax(280px, .78fr) minmax(0, 1.35fr);
  gap: clamp(40px, 6vw, 82px);
  align-items: center;
}
.motion-copy p:last-child { color: var(--muted); font-size: 18px; }
.motion-stage {
  min-width: 0;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: 28px;
  background: #000;
  box-shadow: var(--shadow);
}
.motion-stage iframe,
.motion-stage video { width: 100%; height: 100%; display: block; border: 0; }

/* ===== Pricing ===== */
.price-section { background: #fff; }
.price-card { position: relative; padding: 42px; text-align: center; transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease; }
.price-card h3 { margin: 0; font-size: 34px; }
.muted { color: var(--muted); }
.price { margin: 24px 0 30px; color: var(--dark); font-size: clamp(44px, 5vw, 66px); font-weight: 950; line-height: 1; }
.price span { margin-left: 8px; font-size: 18px; }
.recommend { border-color: rgba(0,151,167,.45); }
.tag { position: absolute; top: 18px; right: 18px; padding: 6px 12px; border-radius: 999px; color: #fff; background: var(--brand); font-size: 13px; font-weight: 900; }

/* ===== CTA & Footer ===== */
.cta-section { text-align: center; color: #fff; background: linear-gradient(135deg, #087e91, #06b8b5); }
.cta-section p { font-size: 18px; }
.warranty { opacity: .9; }
.site-footer { padding: 28px 20px; text-align: center; color: #d9e8ec; background: var(--dark); }
.site-footer p { margin: 3px 0; }

/* ===== Reveal ===== */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .65s ease, transform .65s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ===== Laptop / long-header breakpoint ===== */
@media (max-width: 1100px) {
  :root { --header-h: 82px; }
  .site-header { height: var(--header-h); padding-inline: 30px; }
  .brand-logo { width: clamp(225px, 31vw, 300px); }
  .menu-toggle { display: block; margin-left: auto; z-index: 102; }
  .main-nav {
    position: fixed;
    inset: var(--header-h) 0 auto;
    z-index: 101;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0;
    padding: 12px 24px 24px;
    background: rgba(255,255,255,.98);
    box-shadow: 0 18px 34px rgba(8,35,51,.12);
    transform: translateY(-125%);
    opacity: 0;
    visibility: hidden;
    transition: transform .28s ease, opacity .28s ease, visibility .28s ease;
  }
  .main-nav.is-open { transform: translateY(0); opacity: 1; visibility: visible; }
  .main-nav a { padding: 15px 18px; text-align: center; border-bottom: 1px solid var(--line); font-size: 16px; }
  .main-nav a::after { display: none; }
  .hero-media,
  .hero-overlay { inset: var(--header-h) 0 0; height: calc(100% - var(--header-h)); }
  .hero-inner { min-height: calc(100svh - var(--header-h)); }
  .hero-content { width: min(760px, 76%); }
  .feature-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .split { grid-template-columns: 1fr; }
  .copy { max-width: 780px; margin-inline: auto; text-align: center; }
  .check-list { width: min(100%, 620px); margin-inline: auto; text-align: left; }
  .ui-strip { grid-template-columns: repeat(3, minmax(0, 1fr)); width: min(100%, 900px); margin-inline: auto; }
  .motion-inner { grid-template-columns: 1fr; }
  .motion-copy { max-width: 760px; margin-inline: auto; text-align: center; }
  .motion-stage { width: min(100%, 900px); margin-inline: auto; }
}

/* ===== Tablet ===== */
@media (max-width: 767px) {
  :root { --header-h: 72px; }
  .site-header { height: var(--header-h); padding-inline: 18px; }
  .brand-logo { width: min(245px, 69vw); }
  .menu-toggle { font-size: 28px; }
  .main-nav { grid-template-columns: 1fr; max-height: calc(100svh - var(--header-h)); overflow-y: auto; padding: 8px 18px 18px; }
  .main-nav a { padding: 12px 14px; }
  .hero { min-height: 760px; }
  .hero-media,
  .hero-overlay { inset: var(--header-h) 0 0; height: calc(100% - var(--header-h)); }
  .hero-bg-video { object-position: 62% center; }
  .video-shimmer { background: linear-gradient(90deg, rgba(3,22,35,.92), rgba(3,22,35,.68), rgba(3,22,35,.22)); }
  .hero-inner { min-height: calc(760px - var(--header-h)); align-items: flex-start; padding: 100px 22px 90px; }
  .hero-content { width: 100%; max-width: 620px; }
  .hero h1 { font-size: clamp(68px, 21vw, 112px); }
  .hero h2 { margin-top: 24px; font-size: clamp(34px, 9vw, 50px); }
  .hero .lead { font-size: 18px; line-height: 1.7; }
  .hero-actions { flex-direction: column; align-items: stretch; max-width: 430px; }
  .hero-actions .btn { width: 100%; }
  .scroll-hint { display: none; }
  .section { padding: 72px 20px; }
  .feature-grid,
  .function-grid,
  .price-grid { grid-template-columns: 1fr; }
  .ui-strip { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
  .spec-row { grid-template-columns: 1fr; gap: 6px; padding: 20px 22px; }
  .price-card { padding: 34px 24px; }
}

/* ===== Small mobile ===== */
@media (max-width: 430px) {
  .hero { min-height: 720px; }
  .hero-inner { min-height: calc(720px - var(--header-h)); padding-top: 82px; }
  .hero h1 { font-size: clamp(62px, 22vw, 94px); }
  .hero h2 { font-size: clamp(31px, 9vw, 42px); }
  .eyebrow { font-size: 15px; }
  .ui-strip { grid-template-columns: 1fr 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}